The invention relates to a method and an apparatus for monitoring a user's activities. In principle, such applications are broadly known today for saving children from viewing offensive pictures, reading offensive texts or listening to offensive music by blocking the offensive content after detecting it. The offensive content is usually detected by using content recognition algorithms on texts, images or audio and/or video streams, and combinations thereof, and classifying the recognized content into predefinable categories. This can be achieved by comparing the recognized content to predefinable violation examples such as keywords and the like.
Different levels of monitoring are used in prior art. Most applications work on a network level, for example, in search engines, internet gateways or proxy servers. However, only content obtained via a network can be analyzed this way. Even then, encrypted data, such as transmitted by the HTTPS protocol or within encrypted e-mails, cannot be analyzed without expensively breaking the code. If once such a monitoring instance has been successfully bypassed somehow, the same offensive content can be consumed locally again and again without control.
A different kind of application is known to monitor data sent to a printer, wherein the sent data are analyzed within a printer driver on an operating system level. If characteristics of bank notes are detected within the sent data, only a part of the data is sent to the printer. Instead of printing the rest, a warning about counterfeit money is output. However, such countermeasures require system administrator privileges to install the appropriate printer driver. It is not possible to install them without permission. Secret monitoring of a user's behavior is not possible thus. Besides, these countermeasures can be circumvented by simply using a different operating system.
In a similar way as said printer driver, some graphics software denies to open files that contain an image of a bank note. This protection can be circumvented by simply using different software.
In enhanced monitoring applications, such as the one described in PCT patent application WO 2005/109883 A2, parents are automatically informed by a portable device about an offense of a user or an attempt to one. The device may also inform about its whereabout using a positioning system.